For the Core i7 to become mainstream, Intel needs to release a greater number of affordable chipsets and DDR3 prices will need to come down dramatically. Only then will people think about making the move.

I for one think that the move to LGA1366 will become affordable by Q3 2009, since Intel will have released their Havendale CPUs and the new P55 chipset by then (hopefully). The main factor in this equation is the price of DDR3 RAM, and if it stays as high as it is now, there is no chance of the i7 becoming as successful in the mainstream market as the Core 2 is right now. Even though an X58 motherboard and an i7 cost pretty much the same as their high-performance Core 2 counterparts, DDR2 is vastly cheaper than DDR3, which makes an LGA775 system far more affordable.